TaeYeon, YoonA, SeoHyun, and HyoYeon dances to Rihanna's 'Work'

SNSD's dance battle is on!!

It started with SeoHyun and HyoYeon dancing to Rihanna's 'Work', and now TaeYeon and YoonA have joined them.  Who's the best?  Below are their amusing clips for you to check out~

Credits:
Tiffany's Snapchat